As California's drought deepens, some question how much water the plant is bottling.

CABAZON, Calif. – In a swath of desert dotted with windmills and creosote bushes, a beige building stands flanked by water tanks. A sign at the entrance displays the logo of Arrowhead 100% Mountain Spring Water, with a stream flowing from a snowy mountain. Semi-trucks rumble through the gates, carrying load after load of bottled water.

The plant, located on the Morongo Band of Mission Indians' reservation, west of the desert resort city of Palm Springs, has been drawing water from a spring in Millard Canyon for more than a decade. But as California's severe drought deepens, some people in the area question whether it's right to sell water for profit in a desert region where springs are rare and aquifers have been declining.

"Why is it possible to take water from a drought area, bottle it and sell it?" asked Linda Ivey, a resident from the nearby city of Palm Desert. "We've got to protect what little water supply we have."

Over the years, the Morongo tribe has clashed with a local water district over the bottling operation, and has tried to fend off a long-running attempt by state officials to revoke a license for a portion of the water rights. However, those disputes haven't soured a deal with Nestlé Waters North America Inc., the largest bottled water company in the United States, which leases land from the tribe.

The Desert Sun has made numerous requests to tour the plant but none have been granted. Nestlé and the tribe did not answer questions about how much water is bottled there each year.

As a sovereign nation, the Morongo Indians are exempt from oversight by local water agencies and don't have to report data on groundwater pumping or well levels. Without that information, it's difficult to assess how the bottling plant is affecting the local water supply.

There was a time when Nestlé released annual reports showing how much water was being pulled from the spring in Millard Canyon, but those reports stopped in 2009. Since then, local water agencies have had to estimate how much water being pumped out of the canyon. The Morongo tribe has reported some information to the state, saying in one recent report that about 200 million gallons — enough water for 400 typical desert homes — was pumped from Millard Canyon in 2013.

Several years ago, water researcher Peter Gleick was permitted to visit Millard Canyon. Inside, he saw a bottling plant larger than seven football fields. In the canyon, a small stream flowed among the cottonwood trees.

"The reason this particular plant is of special concern is precisely because water is so scarce in the basin," Gleick said. "If you had the same bottling plant in a water-rich area, then the amount of water bottled and diverted would be a small fraction of the total water available. But this is a desert ecosystem."

Before the bottling plant opened, the spring in Millard Canyon was once used as a source of local drinking water. Then, in the early 2000s, the Cabazon Water District sold the spring water rights to the Morongo Tribe for $3 million. Soon afterwards, the tribe announced a 25-year deal with the Perrier Group of America, owned by Nestlé, to produce Arrowhead water.

Since then, the bottling plant on the Morongo reservation has stirred suspicions and generated debate. Some residents say bottling water is a poor use of the desert's limited supply, especially during one of the worst droughts in California's modern history. Others argue the plant creates jobs and fuels the local economy.

Calvin Louie, the Cabazon Water District's general manager, sees both sides of the dispute. The aquifer in Cabazon has been declining significantly during the drought, and Louie said it would help efforts to manage the area's groundwater if the tribe and other owners of private wells would provide information about how much water they're using.

"Arrowhead provides a lot of jobs, and that helps the economy. On the other hand, Arrowhead has a reputation of going into small communities and taking advantage — and basically, pump them dry and good to the last drop," Louie said. "Everybody affects the aquifer, the water level, but who's to blame? Well, you know, when you don't have the data and when you have no groundwater management, it's a shot in the dark."

Michael Fisher, a spokesman for the Morongo tribe, responded to questions about the bottling plant with an email statement. Fisher insisted that the tribe has a "long history of caring for the environment," and that the partnership with Nestlé has created more than 250 jobs.

"As responsible stewards of the environment, Morongo works carefully with Nestlé to monitor the plant operations and conduct recharge and other environmental programs to ensure that these water resources remain healthy and reliable for future generations," Fisher wrote.

Nestlé said in an emailed statement that its Cabazon facility is "designed and managed" as to prevent harm to the local groundwater, particularly in light of the California drought.

Contributing: Robert Hopwood, Lynne Stephenson and Brett Kelman of The Desert Sun